This invention relates to radio antennas for use on automobiles and automotive vehicles and more particularly to an antenna for receiving AM and FM radio transmissions and for receiving and transmitting CB radio transmissions and which is not readily identifiable as a CB antenna.
CB transceivers are widely used in automobiles, recreational vehicles and the like for two-way communication on and off the highways. It is usually necessary to install an antenna specially designed for transmissions within the CB frequency range, i.e., 26.965-27.405 MHz, to properly use these transceivers. Unfortunately, these antennas are quite distinctive in appearance and thus readily identify a vehicle on which they are installed as containing CB equipment. As a consequence, persons intent on stealing this type of radio equipment can easily identify vehicles in which they are installed and thefts of mobile CB equipment have been common. This equipment, once stolen, is difficult to trace and is seldom recovered.
One approach to the theft problem involves a removable CB antenna which can easily be removed by the owner and hidden when the vehicle is parked. Another approach is to remove the CB transceiver when the driver leaves the car. A disadvantage of these arrangements is that the user must repeatedly remove and reinstall the antenna or the transceiver. A further disadvantage is that these arrangements fail if the driver forgets to or decides not to remove the antenna or transceiver.
A third approach involves replacing the conventional receiving antenna with which most vehicles having a radio are equipped with a "disguise" antenna, i.e., an antenna that looks like a conventional receiving antenna but which is designed for CB frequency operation. While this may satisfactorily disguise the vehicle to a thief, the performance of the vehicle radio, particularly in receiving FM transmissions, is greatly degraded when using present "disguise" antennas.